The MCD cassette (Micro Cassette Disk) was a floppy disk developed in Hungary for use in the MCD-1 floppy disk drive.
The MCD disk and drive were developed as early as 1973 by Marcell Jánosi of BRG (Budapesti Rádiótechnikai Gyár) and granted a domestic patent in 1974. At the time of its development, the 8-inch floppy had only recently been commercially released, and the 5.25-inch floppy had yet to be introduced so the the MCD cassette was ahead of its time. It had a capacity of up to 150 KB.
Rather like the later 3-inch Compact Floppy which was similar in appearance, the MCD cassette's floppy disk is fully enclosed inside a rigid casing with a complex shutter mechanism.
Unfortunately, it was not manufactured until the early 1980s, by which time it faced competition from floppy disk designs such as the 3-inch Compact Floppy and 3.5-inch microfloppy. Apparently some were sold for use with the ZX Spectrum in the UK, but today it is extremely rare.
Dimensions: 75 mm x 100.3 mm x 7.5 mm
Capacity: 150 KB